Speaking of mixed trail etiquette, do you point out incorrect useage?

If you were on the hiker section and came across a biker, would you say something?
If you were on the biker section and came across a hiker, should you point out trail makers?

We live by a mixed multi user dirt singletrack area and I just never know if you should say anything or not. Maybe they don't know? Don't care? Is it worth saying something? Mind your own business if they aren't doing anything bad? What is the right thing to do?

#1. Politely inform them that their presence could lead to trail closures.
#2. Not unless they were hiking on a biking only trail that could cause them harm. Politely suggest they not hike there due to Strav*******s

Hikers and bikers, no. I once had a confrontation with a guy and 2 teens, all on dirt bikes riding the single track in the local park. Telling them hearing a dirt bike in the park would the draw cops in and they'd confiscate their motos wasn't reason enough for them to turn around.

America: where minorities fear their kids getting shot, and white people fear their kids getting shots.

Do they have "biker sections?" Seems trails tend to limit every use but hiking. We do have some trails that specify that biking is only allowed on, say, odd dates, but they allow hiking all the time. I have mentioned to a hiker on an odd-numbered day on one of these trails (who complained loudly about "all the bikes" as we passed her) that if she didn't want to deal with bikes, she should hike on even-numbered days, and we'd all get along better. It was just a point of information, but I'm sure she took it as criticism ...

The only people I've regularly give my advice to as to trail manners are people with dogs are running around and getting in the way. I have yelled "get a leash" or something, but that's about it. Pet peeve, I guess -- I do that if I'm hiking or on my bike, after all.

The trails around here are marked for mtb in one direction and hiking in the opposite direction. I don't say anything to the hikers regardless of the direction they are going. Other than a simple "hello" provided they are being aware of their surroundings and not causing a problem. I do find that bikers riding the wrong way are much more of a nuisance and safety hazard than the occasional trail zombie (clueless hiker), who are themselves just inconvenient.